ML053040206
| ML053040206 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 10/31/2005 |
| From: | Shukla G NRC/NRR/DLPM/LPD4 |
| To: | Oatley D Pacific Gas & Electric Co |
| Shukla G, NRR/ADIP/NRLPO,415-8439 | |
| References | |
| Download: ML053040206 (5) | |
Text
October 31, 2005 Mr. David H. Oatley, Acting Chief Nuclear Officer Pacific Gas and Electric Company Diablo Canyon Power Plant P.O. Box 56 Avila Beach, CA 93424
SUBJECT:
DIABLO CANYON POWER PLANT, UNIT 1 - PHONE CONFERENCE RE:
UPCOMING STEAM GENERATOR TUBE INSERVICE INSPECTION
Dear Mr. Oatley:
Inservice inspection of steam generator (SG) tubes play a vital role in assuring that adequate structural integrity of the tubes is maintained. A phone conference has been scheduled with members of your staff to discuss the results of the SG tube inspections to be conducted during the current Diablo Canyon Power Plant, Unit 1, refueling outage. This phone conference will be scheduled to occur towards the end of the planned SG tube inspection interval, but before the unit exits its refueling outage. Enclosed is a list of discussion points to facilitate this phone conference.
The Nuclear Regulatory Commission (NRC) staff plans to document a brief summary of the conference call as well as any material that you may provide to the NRC staff in support of the call.
Sincerely,
/RA/
Girija S. Shukla, Project Manager, Section 2 Project Directorate IV Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-275
Enclosure:
List of Discussion Points cc w/encl: See next page
October 31, 2005 Mr. David H. Oatley, Acting Chief Nuclear Officer Pacific Gas and Electric Company Diablo Canyon Power Plant P.O. Box 56 Avila Beach, CA 93424
SUBJECT:
DIABLO CANYON POWER PLANT, UNIT 1 - PHONE CONFERENCE RE:
UPCOMING STEAM GENERATOR TUBE INSERVICE INSPECTION
Dear Mr. Oatley:
Inservice inspection of steam generator (SG) tubes play a vital role in assuring that adequate structural integrity of the tubes is maintained. A phone conference has been scheduled with members of your staff to discuss the results of the SG tube inspections to be conducted during the current Diablo Canyon Power Plant, Unit 1, refueling outage. This phone conference will be scheduled to occur towards the end of the planned SG tube inspection interval, but before the unit exits its refueling outage. Enclosed is a list of discussion points to facilitate this phone conference.
The Nuclear Regulatory Commission (NRC) staff plans to document a brief summary of the conference call as well as any material that you may provide to the NRC staff in support of the call.
Sincerely,
/RA/
Girija S. Shukla, Project Manager, Section 2 Project Directorate IV Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-275 DISTRIBUTION:
PUBLIC
Enclosure:
List of Discussion Points PDIV-2 Reading RidsNrrPMGShukla cc w/encl: See next page RidsNrrLALFeizollahi YDiaz-Castillo PKlein RidsOgcRp RidsAcrsAcnwMailCenter RidsRegion4MailCenter (BJones)
Accession No. ML053040206 NRR-106 OFFICE PDIV-2/PM PDIV-2/LA PDIV-2/SC(A)
NAME GShukla LFeizollahi DCollins DATE OFFICIAL RECORD COPY
STEAM GENERATOR TUBE INSPECTION DISCUSSION POINTS PREPARED BY THE OFFICE OF NUCLEAR REACTOR REGULATION PACIFIC GAS AND ELECTRIC COMPANY DIABLO CANYON POWER PLANT, UNIT 1 DOCKET NO. 50-275 The following discussion points have been prepared to facilitate the phone conference arranged with Pacific Gas & Electric Company to discuss the results of the steam generator (SG) tube inspections to be conducted during the current Diablo Canyon, Unit 1, refueling outage. This phone call is scheduled to occur towards the end of the planned SG tube inspection interval, but before the unit completes its inspections and repairs.
The Nuclear Regulatory Commission staff plans to document a brief summary of the conference call as well as any material that is provided in support of the call.
1.
Discuss any trends in the amount of primary-to-secondary leakage observed during the recently completed cycle.
2.
Discuss whether any secondary side pressure tests were performed during the outage and the associated results.
3.
Discuss any exceptions taken to the industry guidelines.
4.
For each SG, provide a description of the inspections performed including the areas examined and the probes used (e.g., dents/dings, sleeves, expansion-transition, U-bends with a rotating probe), the scope of the inspection (e.g., 100 percent of dents/dings greater than 5 volts and a 20 percent sample between 2 and 5 volts), and the expansion criteria. Also, discuss the extent of the rotating probe inspections performed in the portion of tube below the expansion transition region (reference NRC Generic Letter 2004-01, Requirements for Steam Generator Tube Inspections).
5.
For each area examined (e.g., tube supports, dent/dings, sleeves, etc.), provide a summary of the number of indications identified to-date of each degradation mode (e.g.,
number of circumferential primary water stress corrosion cracking indications at the expansion transition). For the most significant indications in each area, provide an estimate of the severity of the indication (e.g., provide the voltage, depth, and length of the indication). In particular, address whether tube integrity (structural and accident-induced leakage integrity) was maintained during the previous operating cycle.
In addition, discuss whether any location exhibited a degradation mode that had not previously been observed at this location at this unit (e.g., observed circumferential primary water stress corrosion cracking at the expansion transition for the first time at this unit).
6.
Describe repair/plugging plans.
7.
Describe in-situ pressure test and tube pull plans and results (as applicable and if available).
8.
Provide the schedule for SG-related activities during the remainder of the current outage.
9.
Discuss the following regarding loose parts:
what inspections are performed to detect loose parts?
a description of any loose parts detected and their location within the SG if the loose parts were removed from the SG indications of tube damage associated with the loose parts the source or nature of the loose parts, if known
October 2005 Diablo Canyon Power Plant, Units 1 and 2 cc:
NRC Resident Inspector Diablo Canyon Power Plant c/o U.S. Nuclear Regulatory Commission P.O. Box 369 Avila Beach, CA 93424 Sierra Club San Lucia Chapter c/o Henriette Groot 1000 Montecito Road Cayucos, CA 93430 Ms. Nancy Culver San Luis Obispo Mothers for Peace P.O. Box 164 Pismo Beach, CA 93448 Chairman San Luis Obispo County Board of Supervisors Room 370 County Government Center San Luis Obispo, CA 93408 Mr. Truman Burns Mr. Robert Kinosian California Public Utilities Commission 505 Van Ness, Room 4102 San Francisco, CA 94102 Diablo Canyon Independent Safety Committee ATTN: Robert R. Wellington, Esq.
Legal Counsel 857 Cass Street, Suite D Monterey, CA 93940 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Harris Tower & Pavillion 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 Richard F. Locke, Esq.
Pacific Gas & Electric Company P.O. Box 7442 San Francisco, CA 94120 City Editor The Tribune 3825 South Higuera Street P.O. Box 112 San Luis Obispo, CA 93406-0112 Mr. Ed Bailey, Chief Radiologic Health Branch State Department of Health Services P.O. Box 997414 (MS 7610)
Sacramento, CA 95899-7414 Mr. James D. Boyd, Commissioner California Energy Commission 1516 Ninth Street (MS 31)
Sacramento, CA 95814 Mr. James R. Becker, Vice President Diablo Canyon Operations and Station Director Diablo Canyon Power Plant P.O. Box 3 Avila Beach, CA 93424 Jennifer Tang Field Representative United States Senator Barbara Boxer 1700 Montgomery Street, Suite 240 San Francisco, CA 94111